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1.
ACS Sens ; 8(2): 712-720, 2023 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-36749605

RESUMO

Common symptoms of food intolerance are caused by chemical components within food that have a pharmacological activity to alter the motility of the gastrointestinal tract. Food intolerance is difficult to diagnose as it requires a long-term process of eliminating foods that are responsible for gastrointestinal symptoms. Enterochromaffin (EC) cells are key intestinal epithelium cells that respond to luminal chemical stimulants by releasing 5-HT. Changes in 5-HT levels have been shown to directly alter the motility of the intestinal tract. Therefore, a rapid approach for monitoring the impact of chemicals in food components on 5-HT levels can provide a personalized insight into food intolerance and help stratify diets. Within this study, we developed a three-dimensional (3D)-printed electrochemical multiwell plate to determine changes in 5-HT levels from intestinal organoids that were exposed to varying chemical components found in food. The carbon black/poly-lactic acid (CB/PLA) electrodes had a linear range in physiological concentrations of 5-HT (0.1-2 µM) with a limit of detection of 0.07 µM. The electrodes were stable for monitoring 5-HT overflow from intestinal organoids. Using the electrochemical multiwell plate containing intestinal organoids, increases in 5-HT were observed in the presence of 0.1 mM cinnamaldehyde and 10 mM quercetin but reduction in 5-HT levels was observed in 1 mM sorbitol when compared to control. These changes in the presence of chemicals commonly found in food were verified with ex vivo ileum tissue measurements using chromatography and amperometry with boron-doped diamond electrodes. Overall, our 3D electrochemical multiwell plate measurements with intestinal organoids highlight an approach that can be a high-throughput platform technology for rapid screening of food intolerance to provide personalized nutritional diet.


Assuntos
Intolerância Alimentar , Serotonina , Humanos , Serotonina/análise , Íleo/química , Mucosa Intestinal/química , Organoides/química
2.
Animals (Basel) ; 14(1)2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38200830

RESUMO

The current research aimed to evaluate the supplemental effects of iron oxide nanoparticles (IONPs) on production performance, viscera development, blood metabolites, redox status, meat quality, and jejunal histology in broilers. A total of 300 day-old broilers were randomly divided into six groups with five replicates per group. Birds were fed on a corn soybean-based diet supplemented with 0, 20, 40, 60, or 80 mg/kg IONPs or 80 mg/kg of FeSO4 for 35 days. The feed conversion ratio (FCR) was improved in birds supplemented with 60 mg/kg IONPs. The pH24h was lower in birds supplemented with 40 mg/kg IONPs compared to that of the bulk group. Pectoral muscle fascicle diameter and fiber density were significantly increased in 20 mg/kg IONP-supplemented birds compared to those of the bulk group, respectively. The muscle fiber diameter was higher in 40 mg/kg IONP-supplemented birds compared with the bulk group. The jejunal villus height, crypt depth, and villus surface area were significantly increased with 60 mg/kg IONP supplementation, whereas villus width was decreased in birds supplemented with 40 mg/kg IONPs. The villus-height-to-crypt-depth ratio was lower in IONP-supplemented birds compared to the bulk group. IONP supplementation improved the FCR, jejunal, and pectoral muscle morphology without affecting the carcass characteristics and redox status of broilers.

3.
Front Psychol ; 13: 918968, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36300079

RESUMO

Debate on violent games and their effect on aggressive behavior remains inconclusive. This study aims to study the predicting role of cognitive, affective, and behavioral engagement states in violent videogames on aggressive behavior, which remains nebulous to date. We visited gaming zones and administered the study survey to collect data from violent videogame users. We collected 208 valid responses that were further analyzed. The present study used SmartPLS (3.3.3) software to perform partial least squares structural equation modeling (PLS-SEM) analysis in two stages. In the first stage, the measurement model assessment reported that cognitive, affective, behavioral, and aggressive behavior proved to be reliable reflective-formative composite constructs. Whereas, the second phase illustrated that cognitive engagement in violent videogames fails to impact aggressive behavior. The other two engagement states (affective and behavioral) in violent games showed a positive impact on aggressive behavior. Our study contributes to aggressive behavior literature by understanding how violent videogame engagement states impact aggressive behavior, which is crucial to recognize aggression so that steps can be taken toward addressing it. This study also contributes methodologically by utilizing the hierarchical component model (HCM) approach to estimate, specify, and validate the hierarchical structure of higher-order constructs (i.e., consumer violent videogame engagement dimensions (cognitive, affective, and behavioral) and aggressive behavior) as reflective-formative composite models.

4.
J Fungi (Basel) ; 6(4)2020 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-33302535

RESUMO

Early detection is critical to the successful treatment of life-threatening infections caused by fungal pathogens, as late diagnosis of systemic infection almost always equates with a poor prognosis. The field of fungal diagnostics has some tests that are relatively simple, rapid to perform and are potentially suitable at the point of care. However, there are also more complex high-technology methodologies that offer new opportunities regarding the scale and precision of fungal diagnosis, but may be more limited in their portability and affordability. Future developments in this field are increasingly incorporating new technologies provided by the use of new format biosensors. This overview provides a critical review of current fungal diagnostics and the development of new biophysical technologies that are being applied for selective new sensitive fungal biosensors to augment traditional diagnostic methodologies.

5.
Plants (Basel) ; 9(7)2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32679645

RESUMO

The extensive use of nitrogen (N) in agriculture has caused negative impacts on the environment and costs. In this context, two pot experiments were performed under different N levels and harvested at different vegetative stages to assess two popcorn inbred lines (P2 and L80) and their hybrid (F1 = P2 × L80) for the N use, uptake and utilization efficiency (with the inclusion and exclusion of root N content); to find the contrasting N levels and vegetative stages that effect nitrogen use efficiency (NUE) and to understand the relationship between the traits related to NUE. The hybrid and P2 were confirmed better than L80 for all the studied traits. NUE is mainly affected by the shoot dry weight, uptake and utilization efficiency. Extremely low and high N levels were found to be more discriminating for N use and dry weight, respectively. At the V6 (six fully expanded leaf) stage, root N content (RNC) should be considered; in contrast, at the VT (tasseling stage) stage, RNC should not be considered for the uptake and utilization efficiency. The genetic parameter performance for N use, uptake, shoot dry weight and N content could favor the achievement of the genetic gain in advanced segregating generations.

6.
Biosens Bioelectron ; 155: 112094, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32090867

RESUMO

A robust amperometric sensor was developed for the lactate detection in the extracellular matrix of cancer cells. The sensor was fabricated by separately immobilizing nicotinamide adenine dinucleotide (NAD+) onto a carboxylic acid group and lactate dehydrogenase (LDH) onto an amine group of bi-functionalized conducting polymer (poly 3-(((2,2':5',2″-terthiophen)-3'-yl)-5-aminobenzoic acid (pTTABA)) composited with N, S-doped porous carbon. Morphological features of the composite layer and sensor performance were investigated using FE-SEM, XPS, and electrochemical methods. The experimental parameters were optimized to get the best results. The calibration plot showed a linear dynamic range between 0.5 µM and 4.0 mM with the detection limit of 112 ± 0.02 nM. The proposed sensor was applied to detect lactate in a non-cancerous (Vero) and two cancer (MCF-7 and HeLa) cell lines. Among these cell lines, MCF-7 was mostly affected by the administration of lactate transport inhibitor, α-cyano-4-hydroxycinnamate (αCHC), followed by HeLa and Vero, respectively. Furthermore, the effect of αCHC concentration and treatment time on the lactate level in the cell lines were demonstrated. Finally, cytotoxicity studies were also performed to evaluate the effect of αCHC on cell viability.


Assuntos
Técnicas Biossensoriais/métodos , Ácido Láctico/análise , Nanotecnologia/métodos , Polímeros , Animais , Técnicas Biossensoriais/normas , Carbono , Linhagem Celular Tumoral , Ácidos Cumáricos/antagonistas & inibidores , Técnicas Eletroquímicas , Enzimas Imobilizadas , Humanos , L-Lactato Desidrogenase , Sondas Moleculares , Nanotecnologia/normas , Reprodutibilidade dos Testes
7.
Biosens Bioelectron ; 130: 48-54, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30731345

RESUMO

Enzymatic and non-enzymatic amperometric glucose sensors based on nanostructured Au-Ni alloy were prepared and compared in their performance. The hierarchically structured Au-Ni surface was merely used for the non-enzymatic glucose sensor, while glucose oxidase attached poly-3'(benzoic acid) -2,2':5',2'- terthiophene (pTBA) formed on the alloy surface was used as the enzymatic sensor. The fabricated sensor was characterized using surface analysis and electrochemical experiments. In case of the enzymatic sensor, the anodic current of H2O2 generated from the enzyme reaction was used as the analytical signal, while the direct oxidation of glucose was observed on a mere Au-Ni alloy electrode without enzyme immobilization, which shows an excellent catalytic oxidation of glucose even in physiological pH. The potential pulse pretreatment of the sensor surfaces improved the performance, which allowed both the sensors reproducible and reusable (enzymatic sensor: coefficient of variation = 1.82%, n = 5, non-enzymatic: coefficient of variation = 2.93%). The enzymatic biosensor reveals the advantages of increased sensitivity, selectivity, and stability, compared with the non-enzymatic sensor. The linear range of enzymatic sensor was attained from 1.0 µM to 30.0 mM with a detection limit of 0.29 µM. The reliabilities of the sensors were also demonstrated through the glucose analysis in human blood samples, and the result was compared with the commercially available glucometer.


Assuntos
Técnicas Biossensoriais , Glicemia/isolamento & purificação , Técnicas Eletroquímicas , Nanoestruturas/química , Ligas/química , Glicemia/química , Catálise , Glucose Oxidase/química , Ouro/química , Humanos , Limite de Detecção , Níquel/química , Polímeros/química
8.
J Pharm Biomed Anal ; 164: 93-103, 2019 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-30366148

RESUMO

Lung cancer is undoubtedly one of the most serious health issues of the 21 st century. It is the second leading cause of cancer-related deaths in both men and women worldwide, accounting for about 1.5 million deaths annually. Despite advances in the treatment of lung cancer with new pharmaceutical products and technological improvements, morbidity and mortality rates remains a significant challenge for the cancer biologists and oncologists. The vast majority of lung cancer patients present with advanced-stage of pathological process that ultimately leads to poor prognosis and a five-year survival rate less than 20%. Early and accurate screening and analysis using cost-effective means are urgently needed to effectively diagnose the disease, improve the survival rate or to reduce mortality and morbidity associated with lung cancer patients. Thus, the only hope for early recognition of risk factors and timely diagnosis and treatment of lung cancer is biosensors technology. Novel biosensing based diagnostics approaches for predicting metastatic risks are likely to have significant therapeutic and clinical impact in the near future. This article systematically provides a brief overview of various biosensing platforms for identification of lung cancer disease biomarkers, with a specific focus on recent advancements in electrochemical and optical biosensors, analytical performances of different biosensors, challenges and further research opportunities for routine clinical analysis.


Assuntos
Biomarcadores Tumorais/análise , Técnicas Biossensoriais/métodos , Detecção Precoce de Câncer/métodos , Neoplasias Pulmonares/diagnóstico , Técnicas Biossensoriais/economia , Detecção Precoce de Câncer/economia , Humanos , Neoplasias Pulmonares/mortalidade , Prognóstico , Taxa de Sobrevida
9.
Biosens Bioelectron ; 116: 108-115, 2018 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-29860089

RESUMO

Brain-derived neurotrophic factor (BDNF) was detected in the extracellular matrix of neuronal cells using a dual probe immunosensor (DPI), where one of them was used as a working and another bioconjugate loading probe. The working probe was fabricated by covalently immobilizing capture anti-BDNF (Cap Ab) on the gold nanoparticles (AuNPs)/conducting polymer composite layer. The bioconjugate probe was modified by drop casting a bioconjugate particles composed of conducting polymer self-assembled AuNPs, immobilized with detection anti-BDNF (Det Ab) and toluidine blue O (TBO). Each sensor layer was characterized using the surface analysis and electrochemical methods. Two modified probes were precisely faced each other to form a microfluidic channel structure and the gap between inside modified surfaces was about 19 µm. At optimized conditions, the DPI showed a linear dynamic range from 4.0 to 600.0 pg/ml with a detection limit of 1.5 ±â€¯0.012 pg/ml. Interference effect of IgG, arginine, glutamine, serine, albumin, and fibrinogene were examined and stability of the developed biosensor was also investigated. The reliability of the DPI sensor was evaluated by monitoring the extracellular release of BDNF using exogenic activators (ethanol, K+, and nicotine) in neuronal and non-neuronal cells. In addition, the effect of nicotine onto neuroblastoma cancer cells (SH-SY5Y) was studied in detail.


Assuntos
Técnicas Biossensoriais , Fator Neurotrófico Derivado do Encéfalo/análise , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Imunoensaio , Nicotina/farmacologia , Animais , Anticorpos Imobilizados/química , Anticorpos Imobilizados/imunologia , Fator Neurotrófico Derivado do Encéfalo/imunologia , Linhagem Celular Tumoral , Chlorocebus aethiops , Técnicas Eletroquímicas , Ouro/química , Humanos , Nanopartículas Metálicas/química , Nanocompostos/química , Neurônios/efeitos dos fármacos , Polímeros/química , Ratos , Células Vero
10.
Biosens Bioelectron ; 109: 263-271, 2018 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-29571163

RESUMO

The analytical performance of the multi enzymes loaded single electrode sensor (SES) and dual electrode sensor (DES) was compared for the detection of adenosine and metabolites. The SES was fabricated by covalent binding of tri-enzymes, adenosine deaminase (ADA), purine nucleoside phosphorylase (PNP), and xanthine oxidase (XO) along with hydrazine (Hyd) onto a functionalized conducting polymer [2,2:5,2-terthiophene-3-(p-benzoic acid)] (pTTBA). The enzyme reaction electrode in DES was fabricated by covalent binding of ADA and PNP onto pTTBA coated on Au nanoparticles. The detection electrode in DES was constructed by covalent binding of XO and Hyd onto pTTBA coated on porous Au. Due to the higher amount (3.5 folds) of the immobilized enzymes and Hyd onto the DES than SES, and the lower Michaelis constant (Km) value for DES (28.7 µM) compared to SES (36.1 µM), the sensitivity was significantly enhanced for the DES (8.2 folds). The dynamic range obtained using DES was from 0.5 nM to 120.0 µM with a detection limit of 1.43 nM ±â€¯0.02, 0.76 nM ±â€¯0.02, and 0.48 nM ±â€¯0.01, for adenosine (AD), inosine (IN), and hypoxanthine (Hypo) respectively. Further, the DES was coupled with an electrochemical potential modulated microchannel for the separation and simultaneous detection of AD, IN, and Hypo in an extracellular matrix of cancerous (A549) and non-cancerous (Vero) cells. The sensor probe confirms a higher basal level of extracellular AD and its metabolites in cancer cells compared to normal cells. In addition, the effect of dipyridamole on released adenosine in A549 cells was investigated.


Assuntos
Adenosina/isolamento & purificação , Técnicas Biossensoriais , Inosina/isolamento & purificação , Neoplasias/diagnóstico , Células A549 , Adenosina/química , Adenosina Desaminase/química , Eletrodos , Humanos , Hipoxantina/química , Inosina/química , Limite de Detecção , Metabolômica/métodos , Neoplasias/metabolismo , Neoplasias/patologia , Purina-Núcleosídeo Fosforilase/química , Xantina Oxidase/química
11.
Biosens Bioelectron ; 102: 540-552, 2018 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-29220802

RESUMO

Neurotransmitters are important biochemical molecules that control behavioral and physiological functions in central and peripheral nervous system. Therefore, the analysis of neurotransmitters in biological samples has a great clinical and pharmaceutical importance. To date, various methods have been developed for their assay. Of the various methods, the electrochemical sensors demonstrated the potential of being robust, selective, sensitive, and real time measurements. Recently, conducting polymers (CPs) and their composites have been widely employed in the fabrication of various electrochemical sensors for the determination of neurotransmitters. Hence, this review presents a brief introduction to the electrochemical biosensors, with the detailed discussion on recent trends in the development and applications of electrochemical neurotransmitter sensors based on CPs and their composites. The review covers the sensing principle of prime neurotransmitters, including glutamate, aspartate, tyrosine, epinephrine, norepinephrine, dopamine, serotonin, histamine, choline, acetylcholine, nitrogen monoxide, and hydrogen sulfide. In addition, the combination with other analytical techniques was also highlighted. Detection challenges and future prospective of the neurotransmitter sensors were discussed for the development of biomedical and healthcare applications.


Assuntos
Técnicas Biossensoriais/tendências , Técnicas Eletroquímicas/tendências , Neurotransmissores/isolamento & purificação , Polímeros/química , Humanos , Neurotransmissores/química
12.
Biosens Bioelectron ; 98: 364-370, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-28704785

RESUMO

A microfluidic structured-dual electrodes sensor comprising of a pair of screen printed carbon electrodes was fabricated to detect acetylcholine, where one of them was used for an enzyme reaction and another for a detection electrode. The former was coated with gold nanoparticles and the latter with a porous gold layer, followed by electropolymerization of 2, 2:5,2-terthiophene-3-(p-benzoic acid) (pTTBA) on both the electrodes. Then, acetylcholinesterase was covalently attached onto the reaction electrode, and hydrazine and choline oxidase were co-immobilized on the detection electrode. The layers of both modified electrodes were characterized employing voltammetry, field emission scanning electron microscopy, X-ray photoelectron spectroscopy, and quartz crystal microscopy. After the modifications of both electrode surfaces, they were precisely faced each other to form a microfluidic channel structure, where H2O2 produced from the sequential enzymatic reactions was reduced by hydrazine to obtain the analytical signal which was analyzed by the detection electrode. The microfluidic sensor at the optimized experimental conditions exhibited a wide dynamic range from 0.7nM to 1500µM with the detection limit of 0.6 ± 0.1nM based on 3s (S/N = 3). The biomedical application of the proposed sensor was evaluated by detecting acetylcholine in human plasma samples. Moreover, the Ca2+-induced acetylcholine released in leukemic T-cells was also investigated to show the in vitro detection ability of the designed microfluidic sensor. Interference due to the real component matrix were also studied and long term stability of the designed sensor was evaluated. The analytical performance of the designed sensor was also compared with commercially available ACh detection kit.


Assuntos
Acetilcolina/isolamento & purificação , Técnicas Biossensoriais/métodos , Leucemia de Células T/diagnóstico , Nanopartículas Metálicas/química , Acetilcolina/metabolismo , Acetilcolinesterase/química , Cálcio/química , Cálcio/metabolismo , Técnicas Eletroquímicas , Humanos , Leucemia de Células T/patologia , Limite de Detecção , Microfluídica , Linfócitos T/química , Linfócitos T/patologia
13.
Biosens Bioelectron ; 83: 312-8, 2016 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-27132006

RESUMO

Hypoxia inducible factor 1 alpha (HIF1α) overexpression was detected in cancerous cells using an amperometric immunosensor with a nano-bioconjugate. The sensor probe was fabricated by covalently immobilizing the antibody (anti-HIF1α) onto a composite layer of functionalized conducting polymer [2,2:5,2-terthiophene-3-(p-benzoic acid)] (pTTBA) formed on a layer of gold nanoparticles (AuNPs). A nano-bioconjugate with hydrazine and a secondary antibody of HIF1α (sec-Ab2) attached on AuNPs reveals the immunoreaction at the sensor probe through the catalytic reduction of H2O2 by hydrazine at -0.35V vs. Ag/AgCl. Morphology and performance of the sensor probe were characterized using FE-SEM, XPS, EIS, and cyclic voltammetry. The calibration plot at optimized experimental conditions shows a dynamic range of 25-350pM/mL with a detection limit of 5.35±0.02pM/mL. The reliability of the sensor was evaluated using non-cancerous Vero and cancerous MCF-7 cell lysates, where the HIF1α expression was compared with three cancerous cell lines MCF-7, PC-3, and A549. Furthermore, the sensor probe confirms the stable expression of HIF1α in the A549 lung cancer cells when exposing them to hypoxic mimicking agents Co, Ni, and Mn ions. Of these, Co ions show the highest stabilization effect on HIF1α followed by Ni and Mn ions, respectively.


Assuntos
Anticorpos Imobilizados/química , Técnicas Eletroquímicas/métodos , Subunidade alfa do Fator 1 Induzível por Hipóxia/análise , Neoplasias/patologia , Polímeros/química , Tiofenos/química , Benzoatos/química , Técnicas Biossensoriais/métodos , Linhagem Celular Tumoral , Ouro/química , Humanos , Imunoensaio/métodos , Nanopartículas Metálicas/química , Reprodutibilidade dos Testes
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